white101, insurance is a must – doesn’t necessarily have to be a policy for that car, a lot of policies cover you to drive another vehicle 3rd party only. If you check your policy for the company car you might be in luck though obviously if you bend it you still need to fix your own!
You can drive to a pre-booked MOT appointment without a current MOT, I suppose you should must be able to do so without tax as well as you can’t get a tax disc without an MOT.
DISCLAIMER: “Some bloke on the internet said I could do it, your honour” is not currently an acceptable defence in a court of law.